In an effort to encourage biodiversity and attract pollinators, we are frequently tempted to add flowers to our gardens.

Most cities and amateur gardeners use horticultural plants, or plants that have been specifically developed for certain features, such their ornamental value, to embellish green spaces. They could catch the eye of a person because of their vibrant colors, odd shapes, and greater proportions. Yet bees and other pollinators may not always find them useful.

In many cases, the opposite is true: the petunia, a well-known garden flower that is native to South America, originally had five petals. Artificial selection has led to hybrid variants occasionally having 10.

"Big, fluffy, and bright flowers are our favorite. We chose a few species with multiple petals to create more visually appealing flowers. The flower appears to be larger as a result. Yet, in practice, this decision may result in the nectar component, which is essential for pollinators, being extinct. In other instances, the petals may conceal it "explains Stephanie Frischie, a native plant materials expert with the Portland, Oregon-based nonprofit Xerces Society.

The petunia experienced exactly what was described. The nectar-producing portions have largely disappeared in the hybrid "double-flowered" forms as the plants have increasingly focused more energy on their huge, many petals. These plants, chosen for their aesthetic qualities, are now commonplace in our cities. "Until recently, you could observe wild vegetation in our cities, but gradually things changed. Owners of cities started to pick ones that appeal to people. For insects, who are affected by this selection, these criteria are less clear "Frischie argues.

70% of the plant species in Germany are in decline nationwide. For the past 60 years, there has been a decline in species richness at the landscape scale of an average of 1.9% every decade. Several invasive species, many of which are introduced through our gardens, are thought to play a factor in this loss.

Selective breeding is not the only cause of the bee population decline. The importing of "exotic" animals from other countries also contributes to it. Although non-native plants may seem more alluring to people due to their vivid colors, distinctive flower shapes, or cultural significance, insects may not share this opinion.

The majority of Australian cities used to resemble British cities, hence Katherine Berthon, an urban ecologist and postdoctoral fellow at RMIT University of Melbourne, claims that this led to the planting of British species trees in the towns. "Yet, British trees are unique in that they typically shed their leaves in the winter. Australian ones, however, don't. On these non-native plants, pollinators do not recognize anything to eat. Insects are very particular about the stuff they eat, and they don't like it "she claims.

We mistakenly believe that bees can pollinate any bloom, but the majority of them must discover the ideal balance between the chemical characteristics of the plant and their own physiology. Bees are substantially more specialized than generalists, according to Frischie.

Urban ecologist Magali Deschamp works at Marseille University in France. She contributed to the development of an urban park in the city's center that aims to draw Mediterranean and local butterflies. Only four species of Mediterranean butterflies remained in Marseille's center when she began her research ten years ago. A Mediterranean butterfly species called Pacha's caterpillar has vanished from the city. "Only sea buckthorn is used as a host plant by Pacha's caterpillar. No butterfly will remain in a garden to reproduce without it. To draw them in, we grew fresh varieties of local sea buckthorn. The butterflies didn't arrive and claim the location for six years "Deschamp says.

The number of butterfly species in the garden has doubled after ten years of study and gardening. "Just adding horticultural plants can potentially assist city owners combat summer heat waves. Yet, insects won't necessarily benefit from it "Deschamp explains.

And there are other issues besides mosquitoes. Also sensitive to novel situations are plants. When a non-native plant imitates a native one, it may open at the wrong time of year, preventing pollination and successful reproduction. Even though they are of the same species, native American flowers may not bloom at the same time as native European flowers in the spring. Plants, like insects, take time to acclimate to a new habitat. This can occasionally require decades.

Although though some rare exotic plants might occasionally be helpful, planting more native species would ensure that bees could find food in our gardens.Yet, only a tiny fraction of the plants offered for sale by commercial nurseries today are native wild-type species. For instance, a 2017 survey of 14 garden centers in the US's mid-Atlantic region discovered that just 5.75 percent of the plants they sold belonged to this category. Horticultural ones, such as those carefully grown for food or ornamentation, make up the great majority. Native plants take a while to grow, which can deter owners from planting them. For instance, Bath, England-based Donald MacIntyre runs a nursery where native species are grown. "Since gardening is so challenging, many people give up after a few years. Understanding and managing the production are challenging, "He claims.

After completing his studies for a certification in plant genetics, McIntyre began producing native plants in 1980. He claims that while the ecology and biodiversity were already declining, the decrease of native flora was not as severe at the time. He exclusively gathers seeds in untamed areas, such as nature preserves, that have not been used for human activities in many years. Just a small amount of collection of these wild plant populations is permitted, and samples are taken in accordance with a stringent process.

There was no demand when MacIntyre began his endeavor. "Needs are gradually increasing right now," he says. Farmers, infrastructure managers, conservatories, and wildlife reserves make up the majority of MacIntyre's clientele. He sells his goods to a very small number of individual gardeners. "We are few in number. In the UK, I am aware of four additional nursery proprietors "He claims.

Some nations have formed specialized networks of local and indigenous plant growers. Almost 20 years ago, German producers developed the Regiosaaten mark, which ensures the provenance and traceability of local and wild plants. The local label Végétal in France takes a similar tack. In France, the label has 75 members. For the first time since the brand's inception in 2018, 25 new farm applications were made in 2022. These national networks have more recently been joined by the European organization Native Seed. Its objectives are to advance both "adaptation to the European native seed supply chain" and "acceptance of international standards for native seed in ecological restoration."

But in order to expand the selection of plants that are good for pollinators, more than simply plant nurseries must undergo a mental transformation.

According to Frischie, "Landscape designers may be aware that each plant has its unique use." She explains that we must recognize that beauty need not exclusively consist of geometrical forms. "There are both towering and short plants. It's not necessary to create something extremely official "she claims. Garden trash can be helpful to insects as well. For instance, fall leaves on the ground may offer refuge in the winter or summer. She continues, "Insects use them to deposit their larvae or to give heat."

Gardens might not be as colorful in this sense of beauty as they are in ours. Native plants are frequently less colorful and spectacular than alien kinds in Europe and the US. Some gardeners might not be as fond of their more subdued hues. "The owner's garden may appear neglected to nearby residents or bystanders. To avoid misunderstandings, you might add a seat, a small fence, and a few small shelters to the landscape to indicate that the area has not been abandoned "propose Frischie.

Of course, perceptions of what constitutes a beautiful garden have evolved over time, and the most well-liked plants are constantly influenced by the fashions of the day (Read more from BBC Future about how some gardens have survived these whims). We have the ability to alter the vogue for big blooms to better suit our altering goals.

The hardest element will be giving gardeners access to plants that are good for pollinators. According to Berthon, it can be challenging to distinguish between genetically native and non-native specimens.

If you visit a typical nursery market, Frischie continues, you can purchase a native plant, but more frequently than not, these are treated with insecticides to make them bigger and taller. "Although some insecticides just remain at the surface and disappear with watering, others do not and remain on the plant for the whole of its life. Even though it is a natural plant, if you plant it in your garden, it will obliterate pollinators "she claims.

There are choices available for gardeners who want to create a paradise for bees and other insects. People can read up on best practices and shop at nurseries that sell native flora. Today, there is a ton of knowledge available on the topic, claims MacIntyre. For instance, the Wild Flower Society in the UK offers online seminars to impart knowledge about effective gardening techniques for preserving biodiversity in natural places. On its website, Native Seed has created a list of owners of native plant nurseries across Europe.